Coinbase, a 2-year-old company, operates an online service that allows users to buy bitcoin, store it in a digital wallet, and pay merchants with it. The San Francisco-based company is among a flurry of start-ups raising venture capital money to support the virtual currency.

The company was started by Fred Ehrsam, a former Goldman Sachs trader, and Brian Armstrong, a former engineer at Airbnb, the short-term-accommodation rental company. Coinbase makes money by charging users a 1 percent fee to convert dollars into and out of bitcoin. Merchants like it because the fees are less than what they pay to process most credit card transactions.

That's not to say the company won't face some hurdles. Last year the FBI seized millions of dollars' worth of bitcoins from an illicit drug website, and fears still exist that hackers can easily manipulate it. Still, with 1.3 million consumer wallets created and 32,000 merchants on board, Coinbase has been able to attract some big-name backers, including Twitter's Union Square Ventures and Andreessen Horowitz.

On the company's disruptive impact:

"This [bitcoin] network now does something that was never possible before. It removes the necessity of a third party in a transaction."-Fred Ehrsam, co-founder

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